This invention relates in general to test equipment arrangements. In particular, this invention relates to an improved end of line test equipment arrangement having a superheat controller that is configured to replace certain components used in a conventional end of line test equipment arrangement.
U.S. Pat. No. 9,140,613 discloses a superheat controller (SHC). The SHC disclosed therein is a single, self-contained, stand-alone device which contains all the sensors, electronics, and processing capability to automatically detect a fluid type, such as refrigerant, and report the superheat of multiple common fluid types used in residential, industrial, and scientific applications. U.S. Pat. No. 9,140,613 is incorporated herein in its entirety.
FIGS. 3 and 4 herein illustrate a known SHC 10, which is similar to the superheat controller disclosed in U.S. Pat. No. 9,140,613. As shown in FIGS. 3 and 4, the illustrated embodiment of the SHC 10 includes a housing 12 having a body 14, a cover 16, and a fluid inlet member 18. The fluid inlet member 18 may be secured to the housing 12 by a mounting ring 19. The mounting ring 19 attaches the fluid inlet member 18 to the housing 12 portion by a threaded connection. Alternatively, the mounting ring 19 may be attached to the fluid inlet member 18 by any desired method, such as by welding or press fitting. In the embodiment illustrated in FIGS. 3 and 4, the fluid inlet member 18 is a brass fitting having a centrally formed opening that defines a sealing surface 20. When used in a known manner in a conventional heating, ventilating, air conditioning, and refrigeration (HVAC-R) system (not shown), the sealing surface 20 of the SHC 10 may engage a connector in the HVAC-R system to define a metal-to-metal seal.
Known superheat controllers include a pressure sensor as an integral component thereof. For example, the known SHC 10 includes an integrated pressure and temperature sensor 22 having pressure sensor portion 24 and a temperature sensor portion 26 mounted to a printed circuit board (PCB) 28. A superheat processor 30, a data-reporting or communication module 32, and an Input/Output (IO) module 34 are also mounted to the PCB 28. The IO module 34 is a physical hardware interface that accepts input power and reports data through available hard-wired interfaces, such as wires or cables 36, to the superheat processor 30. Target devices that may be connected to the SHC 10 via the IO module 34 are schematically illustrated at 38 in FIG. 4 and may include additional temperature sensors, laptop and notebook computers, cell phones, memory cards, and other devices. Alternatively, the target devices 38 may be connected to the communication module 32 by a wireless connection.
The superheat processor 30 is mounted to the PCB 28 and is a high-resolution, high accuracy device that processes the input signals from the pressure and temperature sensor portions 24 and 26, respectively, of the integrated pressure and temperature sensor 22, detects the fluid type, calculates the superheat of the fluid, and provides an output that identifies the level of the calculated superheat. The superheat processor 30 may also be configured to provide other data, such as fluid temperature, fluid pressure, fluid type, relevant historical dates maintained in an onboard memory (such as alarm and on-off history), and other desired information. Advantageously, the superheat processor 30 maintains a high level of accuracy over a typical operating range of pressure and temperature after a one-time calibration. Non-limiting examples of suitable superheat processors include microcontrollers, Field Programmable Gate Arrays (FPGAs), and Application Specific Integrated Circuits (ASICs) with embedded and/or off-board memory and peripherals.
Conventional end of line test equipment arrangements may be used to test devices such as microvalves, microvalve enabled devices, other electronic fluid valves, and other electronic devices such as pressure sensors and flow sensors after the devices have been manufactured and/or assembled. The conventional end of line test equipment arrangement may include a test stand with one or more of the following test components configured to test at least one operational parameter of a device or unit under test (UUT): a multimeter (to identify and measure input voltage to the UUT), a thermistor, a pressure transducer (to measure input pressure to the device), a pulse width modulation (PWM) driver (to control power to the device), a pressure regulator, a pressure reducer, one or more power sources of electrical power, a computer, and a data acquisition device.
There remains, however, a need in the art for a simplified end of line test equipment arrangement that has fewer test components and is therefore easier to construct and is more efficient.